Characteristics of the Preliminary
IPIP Scales Measuring the Big-Five Domains

Big-Five Domain

Number
of Items

Mean Item
Intercorrelation

Coefficient
Alpha

Correlation
with Markers*

Shorter Scales

I. Extraversion

5 + 5 = 10

.40

.87

.73 [.84]

II. Agreeableness

6 + 4 = 10

.31

.82

.54 [.66]

III. Conscientiousness

6 + 4 = 10

.29

.79

.71 [.90]

IV. Emotional Stability

2 + 8 = 10

.38

.86

.72 [.84]

V. Intellect

7 + 3 = 10

.34

.84

.67 [.80]

Total/Mean

26 + 24 = 50

.34

.84

.67 [.81]

Longer Scales

I. Extraversion

10 + 10 = 20

.34

.91

.76 [.84]

II. Agreeableness

14 + 6 = 20

.28

.88

.57 [.65]

III. Conscientiousness

11 + 9 = 20

.27

.88

.74 [.84]

IV. Emotional Stability

5 + 15 = 20

.35

.91

.74 [.81]

V. Intellect

13 + 7 = 20

.32

.90

.69 [.77]

Total/Mean

52 + 48 = 100

.31

.90

.70 [.78]

Note. [Values in brackets are correlations corrected for
unreliability; these may be underestimates, given that the reliabilities of
the factor markers were assumed to be the same as those of their corresponding
IPIP scales.]

* The 100 unipolar Big-Five factor markers are provided in the following
article:
Goldberg, L. R. (1992). The development of markers for the Big-Five factor structure. Psychological Assessment, 4, 26-42.